I have an 82 380SL and love it! I've had the timing chain replaced with a dual row and even found what I believe to be the last set of metal guides installed. Whew! Just installed the backseat myself about a year ago when my brother-in-law left the top down in the rain and ruined the carpet on the back "shelf". It was practically the same money to replace the carpet or buy the seat. It comes with the seat belts and the attachment points exist in all of the cars. I am very short and thought that if I installed the seat I would be able to ride back there and give my brother-in-law the idot proof lexus to drive next time. The problem is two fold. The leg room is limited but there is also zero head room if the top is up. The dog does appreciate the extra cushioning when she rides back there though . I think I remember reading that the back seat was offered as an option on Euro models. I get 18 mpg around town.